Have you ever questioned if the universe has a limit?
We've always longed to observe space, to learn what secrets and mysteries it hides from us.
We cannot, however, always do it ourselves.
The only way for us to see deep space is to use a space observation station, and NASA
is the one who always does the work for us.
Today, we'll be discussing the James Webb Space Telescope!
It was launched into space to provide humans with a better view of the universe.
One of its missions is to capture the universe's very edge.
What could it discover?
What could be lurking on the edge of the universe?
What impact will it have on humanity?
This adventure will be both fascinating and terrifying.
So what are we waiting for?
Let us all be prepared as we fly to the edge of the universe with the James Webb Space
Telescope.
The James Webb Space Telescope was launched into space and is currently operational.
One of its amazing characteristics is that it is sensitive to infrared light, according
to NASA.
As a result, it can detect even the smallest amount of heat in space.
Furthermore, this telescope is a hundred times better than the historic Hubble telescope.
It’s important to note that it’s Hubble that has provided us with amazing images of
the Universe for over three decades.
This means if James Webb is a hundred times better, then it might easily surpass the record,
especially considering it's designed to snap baby images of the universe.
Although we can't deny that the Hubble has been really useful for us, its operation is
limited.
It couldn’t offer scientists a glimpse of the first galaxies that formed after the Big
Bang.
But, thanks to James Webb, we can finally see it.
James Webb will record light that has traveled through space for up to 13.5 billion years.
That means we could advance our knowledge of the universe hundreds of millions of years
before Hubble!
Isn't it fascinating?
What could be the source of James Webb's immense power?
The first one is its massive primary mirror, which has a diameter of 6.4 meters.
It is made up of 18 smaller parts, covered in a very thin gold coating, that are exactly
aligned together.
Keep in mind that a 24-carat gold, which weighs less than two ounces, reflects infrared light
better than other metals.
Infrared is the light used to see things that are beyond the visible range of human vision.
However, keep in mind that the mirrors are composed of beryllium rather than real gold.
Another secret of the Webb telescope is that it must be kept cool in order to perform properly.
And the five-layer solar shield, which is the size of a tennis court, is the one that
does the work.
The sun's enormous heat would have damaged the telescope's sensors if it weren't for
the shield!
The side of the telescope facing the sun will be around 260 degrees Fahrenheit, while the
opposite side will be roughly 370 degrees below zero, a difference of nearly 600 degrees.
In short, the sun shield works like an SPF for the telescope, protecting it from the
damaging sun’s heat.
However, one flaw of James Webb is that it cannot be repaired when problems develop,
both during launch and operation.
Hubble is capable of such feats.
Five space shuttle crews, for example, have performed routine maintenance on Hubble to
rectify the telescope's initially hazy vision as well as perform repairs and upgrades.
However, this is due to the Hubble being only 340 miles away from Earth.
The James Webb telescope is so far away from Earth, so far away that spacewalking repair
teams would be unable to reach it in the event of system failure.
That means NASA just has one chance to get it perfect before sending it into space.
However, scientists believe that if the right technology is created, they will be able to
create and send a robot to refuel Webb in the future, extending its life.
When it comes to power, NASA expected the telescope to last only ten years, but because
of its flawless launch, there has been enough fuel left that is enough to run the James
Webb for another twenty years!
For the time being, scientists are patiently waiting for Webb's first photos.
And after that, the telescope is believed to be of great help in studying the dark energy
in the universe and as well as help the scientists in understanding the nature of these ancient
things in deep space.
Furthermore, it will help humanity know if there is a possibility of another planet that
can support life, among the numerous exoplanets scattered throughout the universe.
It's fascinating to learn that the James Webb Space Telescope is valued at ten billion dollars,
owing to the outstanding features it possesses.
And what exactly am I referring to here?
Of course, it's the telescope's mirrors and massive solar shield.
Except for James Webb's mirror creator, Northrop Grumman, no one has ever been able to manufacture
a valuable mirror like that of James Webb.
Eye surgeons are now using his technology, and they've created identical software that
can be installed on computers.
The company has made significant progress in understanding how to launch large objects,
such as how they wrap up an enormous sun shield and launch it into space.
However, are you curious as to what astronomers will discover when they try to view the edge
of the cosmos with James Webb?
We've long been curious about what might exist in outer space, yet traveling across the universe
involves not only moving through space but also moving through time.
Before we go any further, we must first consider the universe's dimension, as it is required
before we can determine the universe's edge.
The age of our universe is estimated to be 13.772 billion years.
It is, indeed, pretty old.
Do you want to know how big our universe really is?
Its width is estimated to be 28.5 Giga-Parsecs by scientists today.
But how huge is 28.5 Giga-Parsecs?
To comprehend that number and our cosmos, we must first learn the basic concepts of
astronomical units.
An astronomical unit or AU is the average distance between the sun and the Earth, which
is around 150 million kilometers.
Aside from AU, we need to figure out what a parsec is and how big it is.
A parsec is the longest length of a triangle whose shortest side is 1 AU and the opposite
vertex subtends an angle of one arc second.
If you do the math, 1 parsec is 3.26 light-years, or the distance traveled by light in a year,
which is approximately 9,460,000,000,000 kilometers.
Let us go back to the topic of the vastness of the universe, which is estimated to be
28.5 Giga-Parsecs.
Taking into account the computation, it would be 93 billion light-years or 879,780 times
10 raised to the power of 18 kilometers.
That is very enormous!
With that amount, it's obvious that our cosmos is massive!
Before we continue, I just want to remind you that if you've made it this far in the
video, you're clearly enjoying it.
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I'd like you to take a close look at the figures I mentioned previously.
Is there anything that seems off?
That might be the speed of light and the universe's size!
We are all aware that the speed of light is the absolute highest speed that can be achieved.
That means if the universe is 13.7 billion years old, how does it have a width of 93
billion light-years?
It is important to note that if an object generated shortly after the big bang moved
at the speed of light, it should have traveled no more than 13.7 billion light-years by now.
Where did all the matter beyond this point come from?
This is when Hubble's law comes into play!
According to the law, things detected in distant space are red-shifted.
The term "redshift" refers to the change in the wavelength, usually an increase of light
toward the red end of the spectrum.
But why does the wavelength lengthen?
One reason for this is the universe is expanding!
Yes, this is not just about the fact that only objects move apart from one another,
but the space itself is growing as well!
What is even more shocking is that the expansion is speeding up.
This is why, when calculating the width of the universe, the distance due to space expansion
must be taken into account.
Dark matter and dark energy are thought to play a significant role in this event.
However, it is also safe to say that the universe's edge is clearly not 13 billion light-years
away from Earth, but significantly higher than that!
Despite all of this, I am certain of one thing: we will never see objects in the universe
that are particularly beyond sixteen billion light-years away from Earth.
Yes, we can assume that this is also the universe’s edge.
Have we reached it?
Well, not yet.
In addition, this is the maximum distance at which light could ever reach us.
This means that beyond the edge of the universe, which is sixteen billion light-years, the
spread of space is faster than the speed of light.
In that case, the light will obviously never reach us since it has to travel across an
increasing space.
This also means that any event that occurs beyond the edge mark will forever be unknown
to humanity.
But, because of telescopes like the James Webb Space Telescope, this game has changed.
The GN-Z11 galaxy, which is around 32 billion light-years away from Earth, is the most distant
galaxy ever discovered by James Webb.
We reach what is known as 'The Surface of Last Scattering' roughly 46 billion light-years
from Earth.
The Surface of Last Scattering is the thing that we will see regardless of whatever way
you look.
After recombination and photon decoupling, the first-ever photons of cosmic microwave
background radiation emerged from ‘The Surface of the Last Scattering,’ which looks like
a homogeneous sphere of fog.
It is the genesis of the very first scattering of light, but the last of what we can witness.
Does this mean ‘The Surface of the Last Scattering’ is the ultimate destination
of the universe?
Well, the answer is both yes and no.
Since this is the farthest point in space and time that humans can witness, then it
could be called the edge of the Observable Universe.
What we don’t know beyond this universe is called the Opaque Universe.
This also marks the limit of what humanity can witness but is still free to imagine.
What do you think lies beyond the observable universe?
So far, what we only discovered is what existed at a certain place in space in the distant
past.
A more bizarre question is: what could possibly have happened there right now?
The particle horizon, or the farthest distance one can view into the past, is located at
the edge of the observable universe.
Everything we've seen thus far has been done so with Earth at the center and time-scaled
backward with distance.
This raises the question of whether the cosmos is limitless.
According to Einstein's theory of relativity, a flat world must be endless.
Can we thus conclude that the universe has no beginning or end?
We can't answer it yet since we haven't been able to definitively determine what lies in
the observable universe and beyond it.
What are your thoughts?
What do you think about the universe's edge?
Let us know in the comments section.
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